Fluid-actuated pulsating device



Feb. 5, 1957 E. G. TARRY FLUID-ACTUATED PULSATING DEVICE Filed Feb. 9, 1955 IN VEN TOR. [20250 6 72 80 mgmw A ja u r United States Patent O FLUID-ACTUATED PULSATIN G DEVICE Eldred G. Tarry, Westfield, N. 1., assignor to Wallace & Tiernan Incorporated, Belleville, N. J., a corporation of Delaware Application February 9, 1955, Serial No. 487,198

4 Claims. (Cl. 60-60) This invention relates to fluid-actuated pulsating devices and more particularly to devices whereby a diaphragm or other movable element of an expansible chamber is caused to pulsate under repeated application and withdrawal of a driving fluid which may be a gas such as air, or a liquid.

An important use of such devices is in the actuation of pumping or like instrumentalities, for example in the feeding of a fluid in accordance with the rate or other characteristics of pulsation of the mechanism. Since the pulsating device is in effect of the nature of a fluid-actuated motor, it its manifest that the pulsating element may be employed for a variety of purposes requiring a reciprocating drive.

It is an important object of the invention to provide apparatus of the character described which embodies a novel, etfective and reliable mechanism, especially for control of pulsation, a further object being to afford improved pulsating devices of simple and convenient structure and adapted to a variety of uses.

To these and other ends, certain basic features of the invention comprise the combination of an expansible chamber with an ejector (i. e. a venturi) having a throat capable of developing appropriate suction and arranged for passage by fluid under pressure, together with connections for applying suction from the ejector throat to theexpansible chamber, and supplemental passage means or the like for communicating the fluid under pressure directly to the expansible chamber. The device embraces valve means for controlling the last-mentioned passage or connection, so that the chamber, with its driving diaphragm or other element, is alternately connected to receive fluid under pressure, overcoming the effect of ejector suction, and to have such suction when the supplemental passage means is closed, to the end that suction and supply of liquid under pressure are alternately effected in the chamber for corresponding reciprocation of the diaphragm or equivalent element. The valve means is arranged to be driven in an appropriately repetitive manner, viz. so that there is in effect continuous alternation of the position of the valve means and corresponding pulsation of the diaphragm or the like in accordance with the valve actuation.

As illustrative of these and other features described below, the drawing illustrates one example of the invention, as follows:

Fig. l is a largely schematic view of the pulsating device or system, with the several parts shown in considerably simplified form for clarity of illustration; and

Fig. 2 is a fragmentary view showing the control valve of Fig. 1 in its opposite position.

Referring to the drawing, the device comprises a diaphragm enclosed on one side by a chamber-defining structure 11, so as to constitute an expansible chamber of which the movable element or wall is the diaphragm 10.

An ejector 12 has an inlet or inlet conduit 13 and an outlet or outlet conduit 14 arranged so that as fluid traverses the ejector from inlet to outlet, suction or reduced pressure is developed at the throat 15, the throat being provided with a small open space: or one or more openings. The ejector throat, i. e. exteriorly of the path of flow in the conduit system 13, 14, communicates with the chamber 11, as by a conduit 16.

A supplemental passage between the source of fluid under pressure and the chamber is afforded by the conduit 17, the chamber 18 (shown partly broken away) of the magnetic valve 19, and conduit 20, extending in series to the chamber 11.

While any of a variety of repetitively operable control valve means can be employed, the magnetic device 19 is particularly convenient. It includes a valve member 22, within the casing 18, arranged to seat, as by gravity, on the opening 23 in the bottom of the casing. Other communication with the valve is afforded by an opening 24. Thus the valve may be appropriately included in the line 17-40, for example by connection of the conduit 17 with the opening 24 and the conduit 20 with the opening 23. One example of means for actuating the valve may involve constructing the valve member 22 so that it is wholly or partly a permanent magnet, and providing an armature 25, of soft iron or other impermanently magnetic material, which periodically approaches and retreats from the upper end of the casing 18. Thus the member 25 may comprise a semi-circular element, as shown, mounted on a shaft 26 so that upon rotating the shaft the armature member periodically (e. g. once each turn) comes close to the top of the casing 18, attracting and elevating the magnetized valve element 22 and opening the valve, as seen in Fig. 2. When the member 25 is in its remote position, as seen in Fig. l, the element 22 remains seated in the opening 23, keeping the valve closed. Alternatively, the actuating element, such as member 25, may comprise a permanent magnet, and the valve element 22 may constitute an imperinanently magnetic member.

Although the pulsating device is applicable to actuation by any fluid, either liquid or gas, the device is shown as connected to a supply of gas under pressure, e. g. air, entering the conduit 28, wherein it is advanced under pressure by the blower 29 and after traversing a further conduit section 30, reaches the inlet portion 13 of the ejector 12, such inlet being connected with the conduit 30. If desired, the fluid supply system may include a regulating valve 33. in the conduit 30, arranged to provide appropriately constant or regulated pressure downstream of the valve.

It is contemplated that the shaft 26 be subject to continuing drive, e. g. in a continuous or periodic manner, one example of useful driving means being a fluid-flow responsive meter generally indicated at 32, it being understood that the meter 32 is arranged to rotate the shaft 26 in proportion to flow of fluid in a pipe line 33--34.

For completeness of illustration, means are shown for utilizing the pulsations of the diaphragm 10. Although such means may in some cases involve mechanical con nection or linkage to the diaphragm, a simple arrangement for certain purposes involves structure 36 defining a chamber on the opposite side of the diaphragm and having inlet and outlet passages 37, 38 respectively, with corresponding directional check valves 39', 40. Thus if the inlet 4-1 for the check valve 39 is connected with a source of fluid and the outlet 42 of the valve 40 to a locality for use of such fluid, pulsations of the diaphragm 10 will be effective to change the volume of the chamber 36 periodically and pump fluid, e. g. in successive determinable amounts, for delivery through the outlet 42. Although in some cases appropriate spring loading or the like may be provided for the diaphragm 10 (for example as to increase the force of the pumping stroke when the delivery through conduit 42 is to be elfected against a high pressure) the simple arrangement shown is useful for many purposes where regulated quantities of liquid or gas must be delivered in .a continuing manner.

It will now be seen that with the source of fluid under pressure (such as the blower 29) connected for continuous supply to the ejector inlet 13, the diaphragm it will be reciprocated in accordance with the position of the valve element 22. When the magnet 25 is in upper positions such that the valve 19 is closed, suction or subatmospheric or other reduced pressure is communicated through the line 16 by the ejector throat and withdraws fluid from the chamber 11, causing the diaphragm to retract, i. e. to the right as seen in the drawing. When the valve 19 is opened upon theshaft 26 turning the magnet member to lower positions such as in Fig. 2, fluid under pressure may directly travel from the source through the conduit 17, the valve 19 and conduit 20 to the pulsator chamber 11, thus short-circuiting the ejector suction or overcoming it. In consequence the diaphragm MB is advanced in a driving stroke, the enclosed space of the chamber being enlarged by displacing the diaphragm to the left as seen in the figure. Continuing rotation of theshaft 26 successively closes and opens the valve 19, and corres ondingly applies suction and fluid under pressure at alternate times to the chamber 11. The diaphra gm is thereby reciprocated or pulsed, at a rate determined by the movement of the shaft 26.

Where the pulsator is utilized to afford a pumping or feeding action, for example as in Fig. l, the desired liquid or gas is directly pumped for delivery through the outlet line 42, by virtue of the pump chamber 36 on the opposite side of the diaphragm, together With the associated check valves. The pumping action, i. e. feed of liquid or other fluid, is correspondingly proportioned to the rate of reciprocation of the valve 19. Where it is desired to proportion such delivery to the rate of flow of a master fluid, such as water in a main, gas to be treated, or the like, a shaft 26 is readily driven by a flow-responsive device, such as the meter 32 as shown.

The mechanism thus affords an essentially simple and effective device for producing pulsating or reciprocating actuation of an element such as the diaphragm 16, and conveniently at a rate which may be directly controlled by the rate of drive of the shaft 26 for the valve actuating magnet 25. While the driving means for the valve control element may constitute other motor means of continuous or intermittent character, the illustrated apparatus is notably well adapted for control by a flow meter or the like, for example as schematically represented by the device 32 having connections to drive the shaft 26. In all cases, so long as fluid under pressure is continuously supplied to the inlet of the ejector, and the valve 19 is repetitively operated by automatic means, the pulsating function is achieved at the diaphragm 10, the device in its entirety being simple but highly reliable.

It is to be understood that the invention is not limited to the specific devices herein shown and described, but may be embodied in other ways without departure from its spirit.

I claim:

1. A fluid-actuated reciprocating device comprising movable means, means defining a drive chamber opening on said movable means, fluid-conducting means comprising an ejector having an inlet passage and an outlet passage, the inlet passage being connected to receive fluid under pressure, said ejector having a throat and passage means opening to said throat for communicating a fluid withdrawing lower pressure to the aforesaid drive chamber, supplemental passage means for directing fluid under pressure from the fluid-conducting means to the drive chamber, and means including valve means controlling flow through said supplemental passage means independently of flow through the ejector, for alternately and repeatedly interrupting and initiating fluid flow through said supplemental passage means, respectively to effect withdrawal of fluid'from the drive chamber under the aforesaid lower pressure and introduction of fluid into the drive chamber under pressure, for reciprocating said movable means.

2. In a reciprocating device adapted to be actuated by fluid under pressure, in combination, means defining an expansible drive chamber having a passage for fluid communication thereto, and means for alternately and repeatedly advancing fluid into said chamber through the passage and withdrawing fluid from the chamber through the passage, to eflect repeated expansions and contractions of the chamber, said last-mentioned means comprising an ejector having an inlet having continuous connection to receive the fluid under pressure, an outlet connected for continuous discharge of fluid, and a throat to which the aforesaid passage opens for communication of reduced pressure to the chamber, supplemental passage means connected to receive the fluid under pressure, for delivering said fluid to the chamber under pressure to overcome the reduced pressure communicated from the ejector throat and to expand the chamber, a valve controlling the flow through said supplemental passage means and movable between closed and open positions, and driving means operatively connected to said valve to move it alternately and repeatedly between its closed and open positions while the inlet of the ejector remains connected to the fluid source.

3. A fluid-actuated reciprocating device comprising a diaphragm, means defining a drive chamber on one side of the diaphragm, an ejector having an inlet passage and an outlet passage, the inlet passage being connected to receive fluid under pressure, said ejector having a throat and passage means providing communication between said throat and the aforesaid drive chamber, supplemental passage means for directing fluid under pressure from the inlet passage to the drive chamber, a valve controlling the flow through said supplemental passage means and movable between closed and open positions, and driving means operatively connected .to said valve to move it alternately and repeatedly between its closed and open positions to effect, respectively, alternating application of fluid-withdrawing lower pressure and introduction of fluid under pressure, to the aforesaid drive chamber.

4. A fluid-actuated reciprocating device, comprising means defining an expansible chamber and including a chamber Wall element movable with expansion and contraction of the chamber, and mens for automatically and continuously reciprocating said wall element, comprising means defining a passage for fluid flow and having an inlet and an outlet and comprising an ejector through which the fluid flows from the inlet to the outlet, said passage means being connected to receive the fluid under pressure at said inlet, said ejector having a throat, means defining a passage between said throat and said expansible chamber, means defining a passage for fluid flow from the first-mentioned passage means upstream of the ejector to the expansible chamber, a valve for controlling flow of fluid through said last-mentioned passage means and movable between open and closed positions, and driving means operatively connected to said valve for moving it alternately and repeatedly between its open and closed positions, respectively to initiate and interrupt fluid flow through said last-mentioned passage means, for alternating, successive applications, to the expansible chamber, of the fluid under pressure and of fluid-withdrawing low pressure from the ejector throat.

References Cited in the file of this patent UNITED STATES PATENTS 2,311,229 Herbert Feb. 16, 1943 2,417,994 Sheets Mar. 25, 1947 

